(1).13x=x^2+36
x^2-13x+36=0
(x-4)(x-9)=0
x1=4,x2=9
(2).3x(2x-5)-4(5-2x)=0
3x(2x-5)+4(2x-5)=0
(2x-5)(3x+4)=0
2x-5=0,或者3x+4=0
x1=5/2,x2=-4/3